It's true the Spartan-II program was about biological augmentation but you have all underestimated the effects the MJOLNIR armor has when equipped by a augmented human. The armor "vastly improves" the already improved strength, speed, agility, and duration of the supersoldier. The spartans and their physical attributes and capabilities you all know and love from the video games and the badass parts of the books are not involving the soldiers without armor. the MJOLNIR armor project is parallel to the SPARTAN project. They go side by side. Take the MJOLNIR away from the Spartan and you have a superhuman. That's it.
Now, unrustle your jimmies and get back on topic.